Prestressed concrete pipe with anchors for tying joints

ABSTRACT

A pipe section with a concrete core having joint-forming ends and devices for restraining bolts by which joints between connected pipes are closed and prevented from opening, the pipe core being encircled by a tensioned helical wire wrapping continuous lengthwise of the core pipe over and across the locations of anchors by which the bolt-restraining devices are mounted to the core pipe.

United States Patent Bald [ 51' 3,642,033 [451 Feb. 15, 1972 [54]PRESTRESSED CONCRETE PIPE WITH ANCHORS FOR TYING JOINTS [72] Inventor:Robert E. Bald, Roseland, NJ.

[73] Assignee: lnterpaoe Corporation, Parsippany, NJ.

[22] Filed: June 24, 1970 Ill 1 Appl Nu 49,470

I52] [1.8. CI ..l38/103, l38/l'55, l38/176,

[51 I lnt. Cl ..F16l 21/00, F16! 25/00 [58] Field ofSearch ..l38/103,100, 155, 176; 285/288, 230, 368

[56] References Cited UNITED STATES PATENTS 1,652,418 12/1927 Sherrerd..285/288 Kowalewski et al. ..285/230 Dingledy ..138/155 PrimaryExaminer-Samuel B. Rothberg Attorney-George F. Des Marais [57] ABSTRACTA pipe section with a concrete core having joint-forming ends anddevices for restraining bolts by which joints between connected pipesare closed and prevented from opening. the pipe core being encircled bya tensioned helical wire wrapping continuous lengthwise of the core pipeover and across the locations of anchors by which the bolt-restrainingdevices are mounted to the core pipe. 1

8 Claims, 6 Drawing Figures PAIENTEBFEB 15 I972 FIG. 1

FIG. 2

FIG. 5

R .0 7 ND L V A B I E T R E B O R ATTORNEY PRESTRESSED CONCRETE PIPEWITH ANCI-IORS FOR TYING JOINTS This invention relates to prestressedconcrete pipes and, more particularly, to the type of pipe having highlytensioned wire helically wrapped around a concrete core pipe of a pipesection and which employs devices for supporting draw bolts by which twopipes are drawn together to join them.

In a pipe section having a concrete core pipe which is circumferentiallycompressed by a tensioned wire wrapping it is desirable to have the wirewrapping extend from end to end of the barrel of the core pipe. But ifsuch pipe sections are to be provided with bolts on their outsides todraw together a bell and a spigot of adjoining pipe sections, a problemarises because the supports for the bolts can interfere with thecontinuity of the wire wrapping beyond the supports. The termination ofa wire wrapping short of bolt-supporting means effects loss in the fullbenefit to be derived from continuing the wire wrapping beyond eachofthe bolt-supporting means.

Among the objects of the invention is to provide a pipe section having areinforced concrete core with draw bolt supporting members mounted tothe core pipe and having a tensioned wire wrapping helically placedaround the core pipe and continuing through the areas of attachment ofthe bolt-supporting members to fastening means for the wire nearer andclose to the ends ofthe core pipe.

In its more general aspects, the invention provides in the constructionof high-pressure capacity concrete sections suitable for laying apipeline under water, a concrete core pipe circumferentially compressedby a continuous winding of tensioned wire extending from close to themouth of a bell joint ring to the spigot joint ring at the other end ofthe pipe.

The above, and other objects, features and advantages of the inventionwill be apparent in the following detailed description of illustrativeembodiments thereof which is to be read in conjunction with theaccompanying drawing forming a part of this disclosure, and wherein:

FIG. 1 illustrates two connected pipes employing the inventron;

FIG. 2 is a longitudinal sectional view on line 2--2 of FIG.

FIG. 3 is a transverse sectional view on line 3-3 of FIG. .2;

FIG. 4 is a longitudinal sectional view of a modified form of a drawbolt-supporting device;

FIG. 5 is a longitudinal sectional view of still another modified formof a draw bolt-supporting device; and.

FIG. 6 is an orthographic view of the footing or anchoring member shownin FIGS. 2 and 3.

As shown in FIG. 1, the bell-end of a prestressed concrete pipe section10 is connected to the spigot end of another prestressed concrete pipesection 11. The opening of the joint between the pipe sections isrestrained by a draw bolt 12 supported by a bracket 13 which is held inplace on a support 14 anchored in the core pipe 15 of the pipe section10, and by a bracket 16 which is attached to a support 17 anchored inthe core pipe 18 of the pipe section 11. The pipe section 11 has aspigot joint ring 19, similar to the spigot joint ring 20 of the pipesection 10, and which is entered into a bell joint ring 21 ofthe pipesection 10.

A core pipe may be molded or cast in any conventional manner. As shownin FIG. 2, the core pipe 15 has a water barrier in the form of arelatively thin metallic sleeve 22 which extends between and is weldedto the joint rings at either end, such as the bell joint ring 21, and acomplementary spigot joint ring 20, FIG. 1. The interior of the sleeve22 is lined with concrete 23 and completes the wall thickness of thepipe.

Two or more bolts 12 may be used at a joint, but for subaqueous use twoare placed diametrically opposite one another so that when the pipesections are laid the bolts may be located at the horizontal centerplane or a pipeline in order to permit flexibility of a joint. All ofthe supports and anchoring means for the bolts at both ends of a pipesection are generally similarly constructed.

Referring to FIG. 2, an anchoring member or footing 24 for securing thesupport 14 to the core pipe 15 is set in the exterior surface 26 of thecore pipe. The anchoring member 24 is in the form of a plate having twolegs 27 and 28 bent upwardly therefrom as illustrated in FIGS. 2, 3 and6, but it is evident that the legs may be otherwise attached. Ananchoring member having legs 27' and 28' is similarly set in the otherend of the pipe core. I

A support member 17, similar to the support member 17, is mounted to thecore pipe 15 adjacent its spigot end in the same manner as describedwith reference to the support member 14. The legs of the anchoringmembers project outwardly beyond the exterior surface 26 of the corepipe.

The support members 14 and 17 are welded to the respective pairs ofupstanding legs 27, 28, and 27, 28' after a wire 29 has been helicallywrapped under tension around the core pipe 15 and secured thereto at itsends by anchors, one of which is indicated at 30 in FIG. 2. As is wellunderstood, a tensioned wire is wound around a core pipe after the corepipe has been fully cured, and the wrapping is attached at its ends todevices fastened to the core pipe.

As the wire wrapping is applied the wire is wound helically over thelongitudinal expanse of the plate 24 with the legs 27, 28, projectingbetweenturns of the wrapping. The anchorage is thereby securely lockedin place to the core pipe. As'is customary, the wire wrapping isprotected by a coating 31 of mortar or concrete. The legs 27 and 28 ofthe plate are of sufficient length to extend-through the thickness ofthe protective coating 31.

After the wire has been laid and anchored in place, the turns or coilsof the wire wrapping between the legs 27 and 28 are covered with mortaror an epoxy material which also forms a pad 32 under the support 14.

The bracket 13 has a lug 33 which engages in a transverse groove in thesupport 14. As shown in FIG. 2, .a wedge 34 is provided to preventdisengagement of the lug 33 and the bracket from the support 14, but inlieu thereof the groove may be filled with hardenable cementitiousmaterial to serve the same purpose. A cementitious epoxy material isplaced to form a pad 35 beneath the overhanging ledge of the bracket 13.

The bracket 16 is similarly assembled to the support 17, FIG. 1, and alike bracket is assembled in like fashion to the support 17' whenever ajoint is to be made with another pipe section.

In the foregoing, a detailed explanation has been given with respect tothe bolt-restraining member and anchoring means shown in FIG. 2, and itis to be understood that a like member, as shown at 16 in FIG. 1, ismounted to similar anchoring means at the spigot end of the core pipe.

After the flare or mouth of the bell of a pipe section has been placedaround the spigot of an installed pipe section, a bolt 12 is run througheach pair of aligned brackets, and by taking up on a nut 36 the joint isdrawn home. By backing each nut a few turns flexibility of aclosed-joint is assured.

A modified construction for anchoring a support is illustrated in FIG.4. In this case the anchoring means for a slotted support member 37comprises a plate member 38 which has outwardly extending legs 39 and 40and fingers 41 and'42extending from the central body portion of theplate member. This plate member 38 forms a footing which is completelyencased in the concrete of the core pipe when the core pipe is cast. AU-shape saddle 50 is seated in a recess in the exterior Abolt-sustaining bracket 57 is removably attached to the support member37 and may be made secure thereto by either a wedge 58 or a bolt 59, orby both. In any case the bracket need not be mounted before the pipesection has been readied forjoining. g

The modified form of the invention illustrated in FIG. 5 is shown asembodied in a prestressed concrete pipe 60 having prestressedlongitudinal wires 61 in the wall of the pipe and a prestressed wirewrapping 62. In this embodiment the anchoring plate 63 is mounted andsecured in place in the manner described with reference to the anchoringplate 24 of FIG. 2. After the wire wrapping 62 has been applied thecoils of the wire wrapping between the legs 64 and 65 are covered by aprotective coating 66. A slotted support plate 67 for a bracket 68 ismounted between the legs 64 and 65 to which it is welded. A bolt 69 isprovided for securing the bracket 68 to the support plate 67. Thesupport plate 67 completely underlies the bracket 68.

While the principle of the invention and preferred manners of putting itinto practice have been described hereinbefore, it will be evident tothose skilled in the art that various alterations and substitutions maybe made without departing from the substance of the invention, which isintended to be defined in the following claims.

What is claimed is:

l. A prestressed concrete pipe section comprising a concrete core pipehaving joint-forming ends, a helically wound tensioned wire wrappingaround the exterior surface of the core pipe, protective coatingmaterial covering said exterior surface and said wire wrapping, meansfor restraining axial separation of a joint with another pipe section,said restraining means comprising means for anchoring draw boltsupporting means to said pipe section, said anchoring means having abase portion with an expanse longitudinally of said core pipe greaterthan the pitch of said wire wrapping, said base portion located insideof the inner circumference of said wire wrapping in engagement with saidcore pipe, and means attached to said base portion and projectingradially outwardly therefrom between coils of said wire wrapping forengagement with draw bolt supporting means outside of the outercircumference of said wire wrapping, whereby the wire of said wirewrapping is continuous between and from beyond the opposite extremitiesof the longitudinal expanse of said base portion.

2. A pipe section according to claim 1 wherein saidportion of saidanchoring means is disposed in a recess in the exterior surface of saidcore pipe and held fast by coils of said wire wrapping.

3. A pipe section according to claim 1 wherein said anchoring meanscomprise a plate member having legs extending outwardly therefrom toform a cradle for engaging bolt-supporting means, said plate memberdisposed at the outer periphery of said core pipe and said wire wrappingtraversing the outer surface of said plate member.

4. A pipe section according to claim l wherein said portion of saidanchoring means comprises a U-shape cradle of which the legs of thecradle engage said bolt-supporting means, and a footing wholly containedwithin the concrete of said core pipe, said footing being fixedlyattached to said cradle.

5. A pipe section according to claim 1 wherein said boltsupporting meansare attached to said radially outwardly projecting means.

6. A pipe section according to claim 5 wherein said projecting meansextend to a height outside of the exterior surface of said core pipesubstantially equal to the thickness of said protective coatingmaterial.

7. A pipe section according to claim 6 wherein a filling of hardenedmaterials is contained over said coils of the wire wrapping between saidanchoring means and said bolt-supporting means.

8. A pipe section according to claim 5 wherein said boltsupporting meansinclude a socket member fixed to said anchoring means, and a bracketdetachably connected to said socket member.

1. A prestressed concrete pipe section comprising a concrete core pipehaving joint-forming ends, a helically wound tensioned wire wrappingaround the exterior surface of the core pipe, protective coatingmaterial covering said exterior surface and said wire wrapping, meansfor restraining axial separation of a joint with another pipe section,said restraining means comprising means for anchoring draw boltsupporting means to said pipe section, said anchoring means having abase portion with an expanse longitudinally of said core pipe greaterthan the pitch of said wire wrapping, said base portion located insideof the inner circumference of said wire wrapping in engagement with saidcore pipe, and means attached to said base portion and projectingradially outwardly therefrom between coils of said wire wrapping forengagement with draw bolt supporting means outside of the outercircumference of said wire wrapping, whereby the wire of said wirewrapping is continuous between and from beyond the opposite extremitiesof the longitudinal expanse of said base portion.
 2. A pipe sectionaccording to claim 1 wherein said portion of said anchoring means isdisposed in a recess in the exterior surface of said core pipe and heldfast by coils of said wire wrapping.
 3. A pipe section according toclaim 1 wherein said anchoring means comprise a plate member having legsextending outwardly therefrom to form a cradle for engagingbolt-supporting means, said plate member disposed at the outer peripheryof said core pipe and said wire wrapping traversing the outer surface ofsaid plate member.
 4. A Pipe section according to claim 1 wherein saidportion of said anchoring means comprises a U-shape cradle of which thelegs of the cradle engage said bolt-supporting means, and a footingwholly contained within the concrete of said core pipe, said footingbeing fixedly attached to said cradle.
 5. A pipe section according toclaim 1 wherein said bolt-supporting means are attached to said radiallyoutwardly projecting means.
 6. A pipe section according to claim 5wherein said projecting means extend to a height outside of the exteriorsurface of said core pipe substantially equal to the thickness of saidprotective coating material.
 7. A pipe section according to claim 6wherein a filling of hardened materials is contained over said coils ofthe wire wrapping between said anchoring means and said bolt-supportingmeans.
 8. A pipe section according to claim 5 wherein saidbolt-supporting means include a socket member fixed to said anchoringmeans, and a bracket detachably connected to said socket member.